Description: The possibility of using the evolutionary methods of computation based on genetic optimization algorithm for the development and creation of ferrite radar absorbing coating, increasing the radio absorption of reflecting surfaces and reducing radar cross-section (RCS) within 8-12 GHz range was analyzed. For this purpose selected a number of ferrite materials which frequency depend-ences of the dielectric and magnetic permeabilities were determined experimentally The obtained data of dependencies (f) and (f) were compiled into a database, which served as the basis for a genetic algorithm for finding the most suitable ferrite materials capable of providing maximum radio absorbing capacity and minimizing the radar cross-section in the frequency range of 8-12GHz. For the same purpose, and with the help of the same genetic optimization algorithm, a number of possible sequences of layers from the se-lected ferrite materials were established and their thickness was optimized. For the same purpose, and with the help of the same ge-netic optimization algorithm, a number of possible sequences of layers from the selected ferrite materials were established and their thickness was optimized. For the resulting optimization data were modeled a number of four-layer coatings on the plates of aluminum alloy D16, which is uses in the manufacture of gliders military fighter jets, and that in theory should significantly improve radar-absorbing capacity and reduce the RCS. To verify the validity of the obtained results of optimization and modeling, one type of coat-ings out of possible has been chosen and implemented in practice. During the implementation, the special compositions based on the latex compound PUNTACOL C mixed with ferrite materials were prepared, and then layer-by-layer applied on surface of D16 alumi-num alloy plates. After deposition of coatings, measurements of the radio absorbing ability and the magnitude of the RCS were made. Measurements of radar absorbing ability were conducted by subtracting the reflected energy by specially manufactured device in an anechoic chamber. The RCS measurements were carried out using monostatic radio measurements in the frequency range 8-12GHz in the same anechoic chamber. As a result of measurements it was found that the application of the selected coating significantly in-creases the radar absorbing ability of reflecting surfaces and reduces the RCS in the frequency range 8-12 GHz.
Keywords: radar cross-section, genetic optimization algorithm, fitness function, evolutionary methods of computation.
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